URLFetcher: Skip posting to IO thread if already on IO thread.

content/common/net/url_fetcher_core.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/net/url_fetcher_core.h"
 
 #include "base/bind.h"
 #include "base/file_util_proxy.h"
 #include "base/logging.h"
 #include "base/message_loop_proxy.h"
@@ skipping 313 matching lines @@
       NOTREACHED();
   }
 }
 
 void URLFetcherCore::Stop() {
   if (delegate_loop_proxy_)  // May be NULL in tests.
     DCHECK(delegate_loop_proxy_->BelongsToCurrentThread());
 
   delegate_ = NULL;
   fetcher_ = NULL;
-  if (io_message_loop_proxy_.get()) {
+  if (!io_message_loop_proxy_.get())
+    return;
+  if (io_message_loop_proxy_->RunsTasksOnCurrentThread()) {
+    CancelURLRequest();
+  } else {
     io_message_loop_proxy_->PostTask(
         FROM_HERE, base::Bind(&URLFetcherCore::CancelURLRequest, this));
   }
 }
 
 void URLFetcherCore::SetUploadData(const std::string& upload_content_type,
                                    const std::string& upload_content) {
   DCHECK(!is_chunked_upload_);
   upload_content_type_ = upload_content_type;
   upload_content_ = upload_content;
@@ skipping 569 matching lines @@
       original_url_throttler_entry_ != url_throttler_entry_) {
     destination_url_backoff =
         url_throttler_entry_->GetExponentialBackoffReleaseTime();
   }
 
   return original_url_backoff > destination_url_backoff ?
       original_url_backoff : destination_url_backoff;
 }
 
 }  // namespace content